Process for treating fibers



* UNITED STATES PATENT OFFICE.

JOHN H. PICKUP, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR 0F ONE-HALF TO GEORGE A. WILSON, OF NEXV YORK, N.

PROCESS FOR TREATING FIBERS.

N 0.1)rawing.

To all whom it may concern Be it known that I, JoriN H. PICKUP, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented new and useful Improvements in Processes for Treating Fibers, of which the following is a specification.

hIy invention relates to the preparation of vegetable fibers, both for spinning and for paper making and consists in a new process whereby species or fibers heretofore considered useless for such purposes by rez son of their extreme coarseness and brittle nature, are softened and refined to a state whereby the spinning may be carried on.

While my new process may be applied. to the fibers obtained from various genera and their numerous species, I have found that it is particularly valuable, in connection with fibers obtained from plants of the genus Agave and the genus Yucca.

The fibers obtained from the above men tioned types of plants and their several species have heretofore, as far as I am aware,.l')een used only for the manufacture of brushes, bagging and cordage; the use of the fibers beingrestricted to these iudus tries because of its extreme harshness, stiffness, and bristle-like character. The fibers of the above mentioned plants have also been used as a substitute for animal bristles.

By my process the above mentioned fibers are converted into a soft, pliable, and almost silky state whereby they are particularly adaptable for. spinning for textile purposes and for the manufacture of paper.

Referring now to the practice of my process, the fibers upon which I apply the same are obtained in the usual and well known manner from the leaves of the above mentioned plants, are generally from eighteen inches to two feet in length (when the i (we Lechuyuilla is used) and comprise the outer starchy skin or coating which incases a number of entwined strands; It is probably due in a great measure to this skin or coating that the fiber has such a brittle character and therefore I seek first to remove the skin or coating and other undesirable constituents of the fiber. To this end a quantity of the fiber is placed in vats and the fiber is covered with water which is maintained at to degrees Fahrenheit. The fiber is allowed to stand Specification of Letters Patent.

Patented Aug. 24, 1920.

Application filed March 19, 1919. Serial No. 283,464.

and ferment from two to four days; the liquid being then drawn off and the fiber thereupon pressed in order to separate all loose matter from the same. The above. step removes a great portion of the skin from the fiber and also removes matter which I believe to be citric acid alcohol. Iowever, the fiber is still quite brittle, :1 large amount of the skin still remains on the same, and there is as yet an undesirable amount of juice.

In. order to eliminate the juice and skin, I next wash the fiber thoroughly in water and after squeezing the same, enter itinto a solution of slack lime, the solution being of any desired strength. In this connection I have found that a solution of from is one of very satisfactory strength. The lime penetrates the fiber and disintegrates the dirt, skin and other substances which it is desirable to eliminate and at the same time has no harmful effect on the fiber.

I subsequently remove the filler from the lime solution and after squoeaing it and without washing, place the fiber in a high pressure keir or revolving tank partially filled with water which I boil under steam pressure. Of course the period during which the fiber is thus boiled may be varied, but I have found that when boiled from three to five hours under a pressure of steam varying from twenty to thirty-five pounds,

an admirable result is attained. Attention called to the fact that I place the fiber in the heir after it has been removed from the lime solution without washing, the lime which has penetrated the fiber being allowed to remain therein. The boiling of the fiber in the keir removes the lime which tends to make the fiber somewhat brit le, but after the fiber is removed from the heir, it is still rather muddy and in order to change its color, I thoroughly wash the same andethen enter it into a neutralizing acid bath which tends to lighten the color of the fiber.

The color of the fiber varies through rather wide ranges and for this reason, while one type of bath may be satisfactory for a particular lot of the fiber, it may be desirable to use a bath of different character and strength for another lot or sh pment of different color. I have found that some form of an acid re-agent will attain satisfactory results withall types of fiber, but upon some lots of the fiber I find it desirable to use an acid salt, such as hydrosulfite of soda, upon others a mineral acid such as muriatic or sulfuric, and upon others an organic acid such as acetic. If the fiber is very dark in color, the hydrosulfite of soda may be themost desirable, the sulfuric acid being used if the color is not so dark, and the muriatic and acetic acids being used for the lighter colors. Of course there are other factors determining which of the four re-agents should be used, among these factors being the cost of the reagent, the speed of thebleaching effect desired and the color to which the fiber is to be subsequently dyed. The relative value of each of the above mentioned acids in connection with the factors above mentioned is too well known to those skilled in the art to render necessary further explanation.

After the fiber has been treated with one of the above mentioned acid re-agents, it is thoroughly washed and then placed in a high pressure keir wherein it is boiled in an alkali solution and at the same time thoroughly washed. I have found that a 3% solution of caustic soda gives very satisfactory results. The caustic soda penetrates the fiber and softens the same so that it can be more readily spun and will more evenly take the dye. V

In order to neutralize and eliminate the alkali, I subsequently subject the fiber to an acid re-agent as described in connection with a prior step in my process. As before either the acid salt, mineral acid or organic acid may be used, the same factors determining the selection as in the prior step.

In order to complete the preparation of the fiber for the spinning it is then thoroughly washed to eliminate the acid and then dried in the usual manner whereupon it maybe run through any standard breaker and carding machine to disentangle the numerous strands.

I have found that when vegetable fibers are treated by the above described process there results a fiber of soft, pliable and somewhat lustrous character; a fiber which is peculiarly adaptable for spinning into yarn for textile, knitting or for the manufacture of paper. Further, the fibers resulting from my'process will take dye evenly, and in a word, in a most satisfactory manner. I

As stated before, my process will have the above described results'upon the fibers of plants which heretofore it has been considered impossible to convert into condition for spinning. I refer particularly to plants of the gave genus and to plants known as the Agave Lechugulla. Among other plants, heretofore considered worthless as far as affording fiber for spinning purposes is concerned, and upon the fiber'of which my process has the herein described effect, are the Agave Hetemccmtha, Agave Mexicans (often known as Magueg), and the Palmer; and its numerous species (6. g. (.r'ZOTiOSC, Filamentosa, Baccam).

While I have described my process in detail, it should be understood that there are many variations in the same which would readily'occur'to one skilled in the art and which naturally come within the scope of my invention. It should be understood that I am entitled to such variations of my process as come within the scope of the following claims:

I claim: 7

1. The method of preparing vegetable fibers for spinning which consists in allowing the fiber to stand and ferment in a hot bath for an extended period, then entering the fiber into a solution of slack lime, then boiling the fiber under pressure, and subsequently subjecting the fiber alternately to acid and alkaline baths.

2. The method of treating fibers which consists in allowing a quantity of the fiber to ferment in a body of heated water; submitting'the fiber to a solution of slack lime; treating the fiber with an acid reagent;

entering the fiber into an alkali solution and subsequently eliminating the alkali.

3. The process of preparing fibers for spinning which consists in submitting the fibers to a solution of slack lime, then boiling the fibers under pressure, then subjecting the fibers alternately to acid and alkaline baths, and subsequently washing the fibers.

4. The method of preparing vegetable fibers for spinning which consists in permitting the fibers to stand and ferment in a hot bath for an extended period, then entering the fibers into a lime bath, then successively and alternately subjecting the fibers to acid and alkaline solutions and subsequently washing the fibers.

JOHN 1-1. PICKUP. 

